| Description | Background information Annexins are a family of calcium-dependent phospholipid-binding proteins that preferentially bind phosphatidylserine (PS). Under normal physiologic conditions, PS is predominantly located in the inner leaflet of the plasma membrane. Upon initiation of apoptosis, PS loses its Background information Annexins are a family of calcium-dependent phospholipid-binding proteins that preferentially bind phosphatidylserine (PS). Under normal physiologic conditions, PS is predominantly located in the inner leaflet of the plasma membrane. Upon initiation of apoptosis, PS loses its asymmetric distribution across the phospholipid bilayer and is translocated to the extracellular membrane leaflet marking cells as targets of phagocytosis. Once on the outer surface of the membrane, PS can be detected by fluorescently labeled Annexin V in a calcium-dependent manner.In early-stage apoptosis, the plasma membrane excludes viability dyes such as propidium iodide (PI), 7-AAD. These cells will stain with Annexin V but not a viability dye, thus distinguishing cells in early apoptosis. However, in late stage apoptosis, the cell membrane loses integrity thereby allowing Annexin V to also access PS in the interior of the cell. A viability dye can be used to resolve these late-stage apoptotic and necrotic cells (Annexin V, viability dye-positive) from the early-stage apoptotic cells (Annexin V positive, viability dye-negative). We offer recombinant Annexin V conjugated to a numerous fluorophores, as well as an Annexin V biotin conjugate which can be detected with fluorophore-labeled streptavidin. By binding to PS, fluorophores labeled Annexin V can be used to detect and quantify apoptotic cells via flow cytometry or fluorescence microscopy. The excitation and emission maxima of the Annexin V conjugates are summarized in the following table. Cat.No.Ex/Em (nm)Format1rp226056NABiotin2rp225998343/441AF3503rp225999401/422AF4054rp226057490/525AF4885rp226001590/618AF5946rp226060650/668AF6477rp226002681/704AF6808rp226003752/776AF7509rp226053498/517FITC10rp226004410/455Pacific Blue11rp226006647/665Cy512rp226054650/660APC13rp226055565/575PE14rp226058565/670PE-Cy515rp226059565/774PE-Cy7Precautions1. Please try to avoid light when using to slow down the quenching of fluorescence.2. Propidium Iodide Solution is toxigenic and mutagenic; handle with care.3. Due to the calcium dependence of the Annexin V:PS interaction, it is critical to avoid buffers containing EDTA or other calcium chelators during Annexin V experiments.Instruction for use1. Dilute 10X Binding Buffer (A1372288) to 1X using distilled water (1 mL 10X Binding Buffer + 9 mL ddH2O).2. Wash cells twice with cold PBS and then resuspend the desired amounts of cells in Annexin V Binding Buffer at a concentration of 1.0-5.0 x 106 cells/mL.3. Add 5 µL of Annexin V-AF350 to 100 µL of the cell suspension. Stain with a viability dye, such as PI (P1373641; P1372285), 7-AAD (A1372406), or DAPI (D1372407) dyes, if desired.4. Gently vortex the cells and incubate for 10 min at RT (25°C) in the dark.5. Add 100 µL of 1X Binding Buffer to each assay. Analyze by flow cytometry within 1 hr... Read More | Mammalian lactate dehydrogenases (LDH) exist as five tetrameric isozymes composed of combinations of two different subunits. The H subunit predominates in heart muscle, which is geared for aerobic oxidation of pyruvate. The M subunit predominates in skeletal muscle and is concerned more with Mammalian lactate dehydrogenases (LDH) exist as five tetrameric isozymes composed of combinations of two different subunits. The H subunit predominates in heart muscle, which is geared for aerobic oxidation of pyruvate. The M subunit predominates in skeletal muscle and is concerned more with anaerobic metabolism and pyruvate reduction.Catalyzes the interconversion of pyruvate and lactate with concomitant interconversion of NADH and NAD+Recombinant rabbit muscle Lactate Dehydrogenase produced in E.Coli. Chromatographically purified. A lyophilized powder... Read More | Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description:CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining.Description:CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard phenotype marker for the identification of T cell populations. Mature feline CD4 consists of a 388 amino acid (aa) extracellular region containing four immunoglobulin-like domains, a 22 aa transmembrane segment, and a 40 aa cytoplasmic domain. Within the ECD, feline CD4 shares 70%, 58%, 50%, and 48% aa sequence identity with canine, human, mouse and rat CD4, respectively. CD4 is expressed along with CD8 on double positive T cells during their development in the thymus. Either CD4 or CD8 expression is then lost, giving rise to single positive (SP) CD4+ or CD8+ mature T cells. CD4+ SP cells, also known as T helper cells, further differentiate into multiple subsets of CD4+ cells including Th1, Th2, Th17, Tfh, and Treg cells which regulate humoral and cellular immunity. CD4 is reexpressed on circulating CD8+ T cells upon activation and contributes to their cytotoxic effector activity. In human, CD4 is additionally expressed on macrophages, neutrophils, monocytes, NK cells, and neurons and glial cells in the brain. Similar CD4 distribution between species cannot be assumed as demonstrated by its presence on macrophages in human and rat but not in mouse. CD4 binds directly to MHC class II molecules on antigen presenting cells. This interaction contributes to the formation of the immunological synapse which is focused around the TCR-MHC class II-antigenic peptide interaction. Palmitoylation of two cysteine residues in the cytoplasmic tail of CD4 promotes the localization of CD4 in lipid rafts and its ability to augment TCR signaling via activation of the tyrosine kinase Lck. CD4 also functions as a chemotactic receptor for IL-16 and, in human, as a coreceptor for the gp120 surface glycoprotein of HIV-1... Read More | Purity:>90%, by SDS-PAGE visualized with Coomassie® Blue Staining.Implicated in the control of cell proliferation and cellular aging. May also act as a chaperone | Purity>90% SDS-PAGE.Background:Luteinizing Hormone (LH) is a 42 kDa heterodimer belonging to the glycoprotein hormone family. It is composed of noncovalently linked glycosylated alpha and beta chains. The alpha subunit (CG alpha ) is also a component of Follicle-Stimulating Hormone (FSH), ThyroidPurity>90% SDS-PAGE.Background:Luteinizing Hormone (LH) is a 42 kDa heterodimer belonging to the glycoprotein hormone family. It is composed of noncovalently linked glycosylated alpha and beta chains. The alpha subunit (CG alpha ) is also a component of Follicle-Stimulating Hormone (FSH), Thyroid-Stimulating Hormone, and Chorionic Gonadotropin. The unique beta subunit confers the protein’s specific biological action and is responsible for the interaction with its receptor. The approximately 20 kDa human CG alpha subunit shares 73% and 72% amino acid (aa) sequence identity with the mouse and rat orthologs, respectively. The approximately 18 kDa human LH beta subunit shares 71% and 72% aa sequence identity with the mouse and rat orthologs, respectively. Multiple isoforms of LH exist due to differences in the post-translational glycosylation, sialylation, and sulphation modifications of its subunits. The composition, longevity, and activity of the different LH isoforms vary throughout a woman’s menstrual cycle and reproductive life cycle. LH is produced and secreted by the anterior pituitary gland. Its secretion is controlled by Gonadotropin-Releasing Hormone from the hypothalamus; however, LH secretion can also be stimulated by estradiol. LH works in concert with FSH to regulate female reproduction; FSH stimulates follicular growth and LH induces ovulation. LH also drives formation of the corpus luteum by promoting progesterone production. Additionally, LH has been suggested to stimulate the adrenal gland in postmenopausal women to induce secretion of sulfated DHEA, a precursor to androgens. In the testis, LH induces Leydig cell production of testosterone. Hypersecretion of LH has been shown to occur in women with polycystic ovary syndrome and is associated with an increased risk of infertility and miscarriage. Additionally, increased serum LH levels are associated with decreased cognition and have been implicated in the development and progression of Alzheimer’s disease. receptor into an A-frame... Read More |